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    <title>Document</title>
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<body>
    <textarea name="" id="">等会~</textarea>
    <button disabled>同意(3s)</button>


    <script>
        const div = document.querySelector('div')
        const button = document.querySelector('button')

        let count = 3

        const timer = setInterval(() => {
            count--
            if (count === 0) {
                button.disabled = false
                button.innerHTML = '同意'
                clearInterval(timer)
            } else {
                button.innerHTML = `同意(${count}s)`
            }
        }, 1000)



    </script>
</body>

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